PRAGUE (Reuters) - The first thing Microsoft CEO Steve Ballmer thought of when a Hungarian student attacked him with eggs this week was that he had to keep his suit clean, he said on Thursday.

The student threw three eggs at Ballmer, the head of the world's largest software maker, while he spoke at a university in Budapest on Monday.

He said on Thursday he was later told the student was angry over a Hungarian government tender in which Microsoft was not involved.

"I thought it was a joke... maybe some prank, some theatre from the university. Then I heard a sound -- Boom! And I looked at the board behind me, and I said 'uh oh, I have a problem'," Ballmer said during the Czech leg of his tour through Europe and Israel.

"I thought, 'I have to keep this suit clean' so I ducked under the table because I was worried, egg doesn't clean off very easily."

A video circulated widely on the Internet showed the student shouting and throwing three eggs at Ballmer, who crouched behind the podium. The student then left, escorted by university staff.

Ballmer then continued his speech.

"Oh, he waved to me on the way out, and I waved back," Ballmer said.

It was not the first food attack on a Microsoft executive. Protesters hit company founder Bill Gates with four custard pies in 1999.

(Reporting by Michael Winfrey; Editing by David Fogarty)

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